Exit devices, including vertical rod exit devices, often have a latch device that extends into, and out of, the top and bottom edges of a door. Typically, the latch device is configured to extend away from the door and into a mating recess in a door frame so as to provide a locking engagement that may maintain the door in a closed position. The latch device may also be connected to a push bar or trim by a rod or cable. When the door is to be displaced, the push bar or trim is displaced, which may cause the rod or cable to provide a pushing or pulling force that retracts the latch device from the mating recess in the adjacent structure.
Operation of exit devices often requires that the latch device extend a sufficient distance into the mating recess so that the latch device attains a locked position within the mating recess. The extent to which the latch device is to operably extend away from the door and into a mating recess may differ for different doors and/or different door frames. For example, differences in door heights and/or the depths of mating recesses may alter the distance that the latch device is to extend into the mating recess to reach the locked position. Further, over time, the position of the door relative to the door frame may change. Such changes, which may be due, for example, to door sag and general wear and tear on the door, may also alter the degree to which the latch device is to extend into the mating recess.
The door installer often determines the extended position of the latch device before the door is installed, such as, for example, before the door is hung to the door frame. Thus, for ease of installation, the degree to which the latch device will at least initially extend away from the door is typically initially set while the door is laying in a horizontal orientation. Yet, the actual degree of the extension of the latch device typically is not known until after the door has been hung to the door frame. Further, for at least one type of latch device, the extent to which the latch device extends from the door is at least initially positioned by inserting a pin through one of a plurality of holes in a housing that is mounted to the door, and into a hole of the latch device. Such positioning of the pin often involves the installer trying to feel whether the pin has passed through one of the holes of the housing and into the hole of the latch device. When the degree of extension of the latch device is to be adjusted, the pin is removed from the hole of the latch device and the hole of the housing, and placed, again by feel, into another hole in the housing before being reinserted into the hole of the pin. Thus, the degree that the latch device may be adjusted or trimmed is generally limited to the number and positioning of the holes in the housing.
Further, such adjustments to the degree that the latch device extends from the door generally occur along the same axis as the latch device travels into and out of the mating recess. Yet, reliance on the same axis for these adjustments may preclude the latch device from providing dead-latching capabilities. Further, the absence of dead-latching capabilities may increase the opportunity for unauthorized displacement of the latch device and the resulting unauthorized unlocking of the exit device and/or displacement of the associated door to an open position. For example, the absence of dead-locking capabilities may allow for the latch device to be forcibly retracted by an item, such as, for example, by tools, fingers, or cards, among other items, that engages the latch device through a door gap.